Concrete form



W. C. POLK.

CONCRETE FORM.

Jan. 16, 1923.

2 SHLE l'S-SHEET l.

FILED JULYZ 1921.

W. C. POLK. CONCRETE Foam.

FILED JuLY 2; 1,921..

2 SHEETSQSHEET 2.

gyn/vento@ Patented `lan. 16, l923.

, 'f UNITE Sv i 'WALTER o. Pour,'orIND1ANAPoLIs,:nimma.' .w I.

fconcnnfrnronia T all whom #may concern/:l

citizenofithe UnitedStates, residing'at Indianapolis, inlthe 'countyfof Marion andl State' O Indiana, "have inVented new andv use-ful Improvement-s in Concrete Forms, outv whii'zhy the tollowing'is a .specifieation` The 'object' of iny. 'invention' 'to' vproduce iniprovernen'ts.in an apparatuso'f `general type shown ini'nyPatent'Nuinber 1,225,356,

dated May `8, 1917, forfabricatingcircularr concrete structurenparticularly those which 'are )taper-ed, such'ffou instance as chimneys.

' v .The aecompa'nying drawings illustrate my l invention'.v Fig, "l is va 'perspective view of thefapparatus; Fig. `2 a fragmentary peru-` Spective of portions ofthe, innerandjouter forms; F ig. 3 a fragmentary. plan 4 y @fragmentary 'v"er ti'ca`l..seCtiOn.A v

In tliedrawmgs.. indicates a mast upon which is-'m'ounted a vertically movable collar.-

11 provided with a series of radiating varms 12 connected'at-'their outer end s'by'ring 13.

i At one"p`oint"for"a purpose 'which will ap-t space betweenba-rs l14` and 1 5` are plates l16 provided withtwo sets ofspaced`per`fora-,- tionsl17 and 18. The arms 12 are braced by pear; one of thefarms .12 is omitted and the v gap bridged by arer shaped .bars 14' andl'. Secured to eacharm 12, and'bridging the v diago'nalzrods'llQ.connected ,at their-upper ends to the .collar .20, sleeved'upon mast 10. Theouter cylindrical form` is composed ofl a circumferential *series of Loverlapping narrowverticalfarc'fshaped plates 25 each piovidedalong one edge with a stifening 4flan-ge conveniently formed of angleironl Midway in its ywidth.e,ach plate 25 is formed into '.awhollow longitudinal rib 26 and adja'? cent lthis rib, preferably upon the side `.more remote from the' angle iron 27 is a st1ifening rib 28. At itsupper end the hollow rib vbeing threaded to permit' a variation `of spacingg and a consequent, variation of over- Y The perforations ed hooks '.32 adapted tdsupport afbinfdingt strap 33,",which may be tightened'b'y means The -inner 'form isi produced; Aby a @0v ing placed naar@ ferentalseries off narrow are vshapedplates .L l0v stiifenedat lv,one edge' by [a long-it'udin'allf rib 4:1 andy'a't an intermediate point,` byfa" longitudinal rib [42. -Tlieplat'es 40"` areare` l shaped upon 'la 'y radius 'Somewhat E yless theradius of plates 25 a'ndfar\ej toverlappend asshown'in Figi; 2,lbeing'conneoted by bolts),

43 which extendtrorn `one'rib 4.1 -to the yIfile'I @ofthe adjacent plate." fAtfthe upper end l i i tingle iron n which' @Xendsbaweenjthemas 4,1 yandfl2 and isv securedlto" any 'platef16 by` meansl "of bolts 165,f}in'serted' in any perforationslB.

. 'ielili' Qther'soinewhat closerg than are; erforations 17;, 5 the arrangement .E 'being f'such that,` as i Plates 25,52L`I1d 40am siiclclessivelygshiftedin# may be .decrea'sed as the, interna-ll andieXter-p 1;

nal diaineters decreasel .-1

' Supportedfupon the mastiais" einen shiftable collar*,50;supporting@ crossiarm'Y 4 5l,- uponI one endof;which.isfmountedV al trolley .f carria'ge 52 lsupporting an elevator bucket v5,3 which may bewraised and, lowered-31.

through vthey-spiace X, (Figfl) ,L KL"Ilieffarms 12 if form :supports for foot' Aboards l serve as.aworkingplatform:

`collar lsupporting a series of outwardly,- r l and downwardly radiating arms 61 connected at. their outer ends by a ring 62 0f ap j f 100. cured tov said rings 62 and 13 is a circumfe-v ential series of vertical suspension rods 63,y

proximately the diameter of ring 13, and sewhich are extended considerably below ring 13 and connectedv byrings 64; and 65.y "Pro1 jecting upwardly and inwardlyf'rom ring 65 is acircumferential series yof brace bars k68kwhich lform a working'platform about seven feet below the platform 54C.v VThe .verti-y cal suspension rods 63 .and the ysuper-struc- 66 connected at their 'upper ends with' crossrv bars 67 forming a Support or'foot boardsture 62'-61 form a housinglupon which'may vof" A `j` .95. Vertical y ad'ustable.uponnilast 10 Vis a `v be placed a canvas cover which will entirely encase the apparatus and, when drawn in at its loweredge below ring 62 will serve as a housing which will permit` work'. to beV car-.t

ried on during freezing weather. This encasing canvas is also useful when carrying on construction at high elevations in windy weather.

y The initial ourvatures of plate 25 approxi-- mate the curvature of thev largestdianieter article to be produced, while the initial curvature of plates 40,. approximate the curvature of the smallest :diameter article to be` produced. Each of the plates 25and l0 has a free `edge capable ofs'uflicientlateral dis# toi'tion to permit its being brought into approximation with theY various curves to be produced and the plates thus coordinate to produce a substantially circular article.

There is, however, inthe finished article, a

ridge or olf-set'forined'at each overlap and tliiswfould become very apparent to the observer were' it not for thejeffectthe vertical ribs 70v produced in the ,finished article by reason of hollow ribs Q6 of the formk plates 25,- but these ribs 70 break upv the externaly surface of the article to su'ch an extent as to practically obliterate 'the least, pronoi'inced variations.

I claimas my invention:

1. rlfh'el combination 'Y with mast, of ,t a, frame verticallylmovable on said mast and provided withV a plurality of radiatingarms,

a forni carryingplatecarried byeach of said arms, a oircumferenial series 'of overlapping external form plates adjustably attachableto said forni carrying plates, a circumferential series of overlapping internal form plates,

vand means for adjustably connectingsaid internal form plates. V

'2. -Tlie combination'with va mastpofl a frame verticallyv movableyonsaid mast and provided with a plurality of radiating arms,

plates with; the forml carrying a form lcarrying plate carried byeach of said ,armsja lcircumferential series ofoverlapping external form plates. Yadjustably` attachable to said form carrying plates`,"a circumferential series of overlapping internal*y forni plates,'and means for `adjustably connecting said internal form plates with the form carrying plates, a pair of vertical stiff--` vening ribs carried by said form plates, one

of each pair of ribs being arranged at an intermediate point in the width of its plate,

adjustable connections between adjacent ribs of adjacent plates. i

3. The combination with a mast, of. a frame vertically movable on said mast'and provided with a plurality of radiating arms,

arms, a'crcumferential series of overlapping .60 la form carrying plate carried by each of said. l y, t

external form plates adjustably attachable' to said form` carrying plates, a circumferen-v tial series of `overlapping internal form said internal form plates with the vform carrying plates, a pair of vertical stiffenin'gribs carried by Said forni plates,"one ofveacli' pair of ribs `being arranged at :an 1 intermediate L plates, and means for adjustably connecting n t ,y point in 'the width .of itsplate, adjustable connections between. adjacent ribs of adjaV-Y f mast, a pair of col-related concentric formssupported from said mast', and a c'oversiip-iy portingV frame y vertically' adjustable upon said mast.

6. The combination with a,l mast,ofa series of radiating suspension rods vertically adjustable upon said mast,'a circumferenti'al series of suspension rods supported t* thereby, a worlrplatform. supportedby said suspension rods andv upon said mast, and forms 'supported by said frame work.

ln witness whereof, have hereunto set 5 my hand at Indianapolis, Indiana, this twenty-eighth day of April, A. D, one thou-y sand nine hundred and twenty-one.

WALTER o. PoLKj t 

